The goal of the Status and Trends in Receiving Waters element of the RSMP are to measure changes in the Puget Lowland streams and Puget Sound urban shoreline areas as a result of stormwater management. For the Status and Trends element of the RSMP, 81 of 84 eligible Western Washington Phase I and II Municipal Stormwater Permittees chose to participate via the cost sharing program.

RSMP stream sites are selected from EPA’s GRTS randomized Master Sample list. The area of selection was the Puget Sound Lowland Ecoregion with a target on small to mid-size streams. Two distinct strata are being sampled: outside the urban growth area (OUGA) and within the urban growth areas (WUGA).

Each of the 387,237 points contained in the study areas on the Washington Master Sample shapefile (www.ecy.wa.gov/services/gis/data/enviro/mastersample.htm) were evaluated to generate a list of candidate sampling sites within the assessment regions determined for the RSMP. Master sample sites were statistically chosen from the lines on a 1:24,000-scale hydrography frame WDNR watercourses.  The RSMP small stream site selection effort pertains to monitoring within only 1st, 2nd, and 3rd order streams that flow directly or indirectly into Puget Sound. The final assessment area was determined by three geographic areas in the Puget Sound watershed. The first was the EPA Ecoregion level III designated as the “Puget Sound” ecoregion.  The second was the Washington State Salmon Recover Region designated as “Puget Sound”.  The RSMP small stream sites are those Master Sample sites that were contained by both the Puget Lowlands Ecoregion within the Puget Sound Salmon Recovery Region (PLSRR).  The two evaluation strata for the RSMP small streams monitoring design are the PLSRR stream reaches that fall Within and Outside of the designated Urban Growth Areas (UGA) as defined by the Growth Management Act. 

WUGA: City /UGA regions within the PLSRR and PLE. Sites are located within combined incorporated City boundaries and unincorporated UGAs within the PLSRR and PLE.

OUGA:  Regions within the PLSRR and PLE but outside City/UGA boundaries. These sites are located outside of combined incorporated City boundaries and unincorporated UGA within the PLSRR and PLE

The sources of the geographic information used include:

• www.epa.gov/wed/pages/ecoregions/level_iii_iv.htm#Level%20III

• www.rco.wa.gov/salmon_recovery/regions/regional_orgs_map.shtml

• http://www.ecy.wa.gov/services/gis/data/data.htm

All three layers (Ecoregion, Salmon Recovery and UGA) are available from Ecology’s GIS and were used for the RSMP small streams list.